Initial QSfera import

Server/services/thumbnails/pkg/thumbnail/generator_vips.go

@@ -0,0 +1,84 @@
+//go:build enable_vips
+
+package thumbnail
+
+import (
+	"bytes"
+	"image"
+	"strings"
+
+	"github.com/davidbyttow/govips/v2/vips"
+	"github.com/qsfera/server/services/thumbnails/pkg/errors"
+	"golang.org/x/image/bmp"
+)
+
+// SimpleGenerator is the default image generator and is used for all image types expect gif.
+type SimpleGenerator struct {
+	crop    vips.Interesting
+	size    vips.Size
+	process string
+}
+
+func NewSimpleGenerator(filetype, process string) (SimpleGenerator, error) {
+	switch strings.ToLower(process) {
+	case "thumbnail":
+		return SimpleGenerator{crop: vips.InterestingAttention, process: process, size: vips.SizeBoth}, nil
+	case "fit":
+		return SimpleGenerator{crop: vips.InterestingNone, process: process, size: vips.SizeBoth}, nil
+	case "resize":
+		return SimpleGenerator{crop: vips.InterestingNone, process: process, size: vips.SizeForce}, nil
+	default:
+		return SimpleGenerator{crop: vips.InterestingAttention, process: process, size: vips.SizeBoth}, nil
+	}
+}
+
+// ProcessorID returns the processor identification.
+func (g SimpleGenerator) ProcessorID() string {
+	return g.process
+}
+
+// Generate generates a alternative image version.
+func (g SimpleGenerator) Generate(size image.Rectangle, img interface{}) (interface{}, error) {
+	var m *vips.ImageRef
+	var err error
+	switch img.(type) {
+	case *image.RGBA:
+		// This comes from the txt preprocessor
+		var buf bytes.Buffer
+		if err = bmp.Encode(&buf, img.(*image.RGBA)); err != nil {
+			return nil, err
+		}
+		m, err = vips.NewImageFromReader(&buf)
+		if err != nil {
+			return nil, err
+		}
+
+	case *vips.ImageRef:
+		m = img.(*vips.ImageRef)
+	default:
+		return nil, errors.ErrInvalidType
+	}
+
+	if err := m.ThumbnailWithSize(size.Dx(), 0, g.crop, g.size); err != nil {
+		return nil, err
+	}
+
+	if err := m.RemoveMetadata(); err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}
+
+func (g SimpleGenerator) Dimensions(img interface{}) (image.Rectangle, error) {
+	switch img.(type) {
+	case *image.RGBA:
+		m := img.(*image.RGBA)
+		return m.Bounds(), nil
+	case *vips.ImageRef:
+		m := img.(*vips.ImageRef)
+		return image.Rect(0, 0, m.Width(), m.Height()), nil
+	default:
+		return image.Rectangle{}, errors.ErrInvalidType
+	}
+}